From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Date: Wed, 13 Oct 2010 15:55:43 -0400
Subject: lvconvert: provide useful error when snapshot-merge target missing
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References: <20101013185302.GA2944@redhat.com>
 <4CB6034D.5080603@redhat.com>
Message-ID: <20101013195543.GB3172@redhat.com>
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On Wed, Oct 13 2010 at  3:06pm -0400,
Milan Broz <mbroz@redhat.com> wrote:

> On 10/13/2010 08:53 PM, Mike Snitzer wrote:
> > Convey need for snapshot-merge target in lvconvert error message and man
> > page.
> 
> > --- a/lib/metadata/segtype.h
> > +++ b/lib/metadata/segtype.h
> > @@ -66,6 +66,7 @@ struct segment_type {
> >  
> >  struct segtype_handler {
> >  	const char *(*name) (const struct lv_segment * seg);
> > +	const char *(*target_name) (const struct lv_segment * seg);
> >  	void (*display) (const struct lv_segment * seg);
> >  	int (*text_export) (const struct lv_segment * seg,
> >  			    struct formatter * f);
> 
> I think this will break shared (external) segment module ABI.
> Nobody uses that but worth to mention it.
> (See e.g. lib/mirror and --with-mirrors=shared)

OK, I'm not familiar with that ABI concern.  Any ideas on how I avoid
this breakage?  Add function pointer to end of struct?  Or any change
to struct will be taken as breakage?

Mike